Investment GradeIG
Investment grade describes bonds rated BBB− or higher by S&P (Baa3 or higher by Moody's), meaning agencies see a relatively low risk of default. These bonds pay lower yields than high-yield debt but are held widely by conservative investors.
The bond market is split by one line: investment grade above, high yield below. That line decides which investors can buy a bond, how much interest the issuer pays and how prices react to bad news. This entry explains the investment-grade cutoff, why it matters and what happens when a bond falls below it.
- Category
- Bonds and Interest Rates
- Reading time
- 3 min
- Also called
- Investment-grade bonds, IG bonds, High-grade bonds
- Updated
Investment grade in plain words
S&P classes bonds rated BBB− or higher as investment grade; Moody's uses Baa3 or higher.1
Bonds rated BB or below on S&P's scale are not investment grade because of the higher potential for default.2
A credit rating is an agency's opinion of a borrower's ability and willingness to repay on time.3
How to use the investment-grade line, step by step
Check the rating
BBB−/Baa3 or above. See Credit Rating.
Compare yields
IG pays less than high yield. See High-Yield Bonds.
Check the spread
Extra yield over Treasuries. See Credit Spread.
Watch BBB bonds
Closest to the cutoff.
Know mandates
Many funds hold only IG.
Plan for downgrades
Forced selling can follow.
Worked examples
Example 1 — Yield comparison
Lower yield, lower riskTreasury 4.2%, A-rated corporate 5.0%, BB-rated corporate 6.8%.
| IG spread | 80 bps |
| High-yield spread | 260 bps |
Investment-grade bonds offer smaller spreads because their default risk is seen as lower.2
Example 2 — Falling angel
−8%A BBB− bond worth $100 is cut to BB+; IG-only funds must sell and the price drops to $92.
| Price change | −8% |
BB+ sits below S&P's BBB− investment-grade minimum.1 Funds restricted to investment grade may therefore have to sell.
Example 3 — Interest income
Risk vs income$50,000 in an IG bond fund yielding 5% vs a high-yield fund yielding 7.5%.
| IG income | $2,500 |
| HY income | $3,750 |
| Extra for more risk | $1,250 |
Higher income from lower-rated bonds is pay for higher default risk. See High-Yield Bonds.
Investment grade vs high yield
| Aspect | Investment grade | High yield |
|---|---|---|
| S&P rating | BBB− and above | BB+ and below |
| Default risk | Lower | Higher |
| Yield | Lower | Higher |
| Typical holders | Pensions, insurers, banks | Specialist funds |
Why investment grade matters
Conservative portfolios
Steady income with lower risk. See Corporate Bonds.
Regulatory capital
Banks and insurers favour IG.
Fund mandates
Many funds may hold only IG.
Credit cycles
Watching BBB downgrades. See Business Cycle.
Advantages and disadvantages
Advantages
- Lower default risk.
- Broad, liquid market.
- Steady income.
Disadvantages
- Lower yields.
- Still sensitive to interest rates.
- Downgrade risk near the cutoff.
Going deeper
Read as far as you need. Each level builds on the one before it.
Different symbols
Beginner
Each agency sets its own minimum for investment grade, such as BBB− at S&P and Baa3 at Moody's.1
The BBB bulge
Intermediate
A large share of IG debt sits at BBB, just above the cutoff, so a wave of downgrades could flood the high-yield market. See Credit Rating.
Rate vs credit risk
Advanced
Investment-grade bond returns depend more on interest rates than on defaults, unlike high-yield bonds. See Interest Rate.
Common mistakes
Assuming IG can't default
Lower risk isn't zero risk.
Ignoring duration
Long IG bonds swing with rates.
Chasing BBB yields blindly
They're closest to downgrade.
Mixing agency scales
Check each agency's symbols.
Check your understanding
Test yourself before moving on. Each answer comes with an explanation.
Key points to remember
- Investment grade = BBB− (S&P) or Baa3 (Moody's) and above.
- Lower default risk, lower yields.
- Many institutions may only hold IG.
- Falling below the line can trigger forced selling.
- IG bonds remain sensitive to rates.
Frequently asked questions
What is a fallen angel?
Are investment-grade bonds safe?
What is a rising star?
Further learning
- Credit Rating
How grades are set.
- High-Yield Bonds
The other side of the line.
- Credit Spread
Pricing credit risk.
Sources
This article is written in our own words. The sources below support the specific facts, rules and figures marked with a number in the text. Links open the original publisher’s page.
- Corporate Finance Institute. Investment-Grade Bonds (opens in a new tab) Checked .
- FINRA. Bonds (opens in a new tab) Checked .
- Corporate Finance Institute. Credit Rating (opens in a new tab) Checked .
Educational content, not financial advice. Examples use hypothetical prices and simplified costs; actual fees, margin rules and regulations vary by broker, market and country. We are not affiliated with any publisher linked above. Last reviewed . Report an error or request a source credit.